Conventionally, various proposals have been made for current-conducting thermal transfer recording method in which ink is transferred to a recording medium by inputting an electrical signal corresponding to an image signal to an ink transfer medium having an anisotropic conductive layer and a heat-generating resistive layer. For example, Japanese unexamined patent publications Sho 56-10479 (1981), Sho 60-259485 (1985) and Hei 1-113276 (1989) describe a printing process using an ink transfer medium having a toner layer adhering to it, which is first fused and then mechanically leveled. Japanese unexamined patent publication Sho 63-297084 (1988) describes a printing process in which toner is attached uniformly to an ink transfer medium by electrostatic force and then ink is transferred to a recording medium in a pattern corresponding to an image signal.
In the first of the above described processes in which toner is held to an ink transfer medium by heat, however, because of the use of heat, there are problems of high power consumption and in that the recording apparatus is inevitably bulky. Although toner is fused to the ink transfer medium by heat and mechanically leveled to form a thin layer, inevitably there are fine irregularities in the ink layer itself. Irregularities also occur with re-inking of ink that is removed in the transfer process. Because of irregularities and because of change in material properties such as electrical conductivity and dielectric constant when toner is fused to form a solid layer, re-inking does not produce a stable ink transfer medium. The second of the above described processes in which toner is held to the ink transfer medium by electrostatic force has problems that toner is not retained well because the retention is done only by electrostatic force. The toner tends to fall off because of vibration and the like, and this leads to problems such as background fogging.